Let's make this clear. Apple was never against the idea of a 7" tablet. Specifically, Jobs did not like the physical size of UI elements that accompanied smaller (than iPad 9.7") tablets at the time. He never said the 7" screen was too small. He said something like "sand paper should be in the box to sand your fingers down" to be able to tap the small UI buttons. The Android OS on tablets was craptastic at the time. It was also pretty craptastic on smartphones. Today, it's made so much progress on both fronts.
Apple Maps. Not a disaster. It worked fine for me on Day 1. Yes, there were some glitches and 3D Flyover imagery issues. But as far as the core functionality was concerned, it was solid. Imagery can be fixed. Core functionality is a bit more difficult. Google Earth is and was no different. They've had close to a decade to fix imagery problems. As far as UI and ease of use, Apple Maps were and is a big win.
Siri. Not a disaster. Those comparing to Google Now are pretty stupid. Google Now and Siri are two different beasts and have two very different goals in mind. Siri is on-demand. Google Now is trying to predict your future based on previous usage behaviors and patterns. Siri is inherently never "ahead of the curve" so to speak. Google Now tries to be but it doesn't always get it right.
As far as Forstall, he did many great things to iOS. He made mistakes sure. But overall, iOS would not be where it is today without him. But with Steve Jobs gone, Apple is going to change whether you like it or not. There's a new CEO. It's Cook's Apple now. And so far, we haven't seen any major changes that can be decidedly those of Tim Cook.